One of the greatest mysteries in reconstructing the history of life on Earth has been the apparent absence of fossils dating back more than 550 million years. We have long known that fossils of sophisticated marine life-forms existed at the dawn of the Cambrian Period, but until recently scientists had found no traces of Precambrian fossils. The quest to find such traces began in earnest in the mid-1960s and culminated in one dramatic moment in 1993 when William Schopf identified fossilized microorganisms three and a half billion years old. This startling find opened up a vast period of time--some eighty-five percent of Earth's history--to new research and new ideas about life's beginnings. In this book, William Schopf, a pioneer of modern paleobiology, tells for the first time the exciting and fascinating story of the origins and earliest evolution of life and how that story has been unearthed.

Gracefully blending his personal story of discovery with the basics needed to understand the astonishing science he describes, Schopf has produced an introduction to paleobiology for the interested reader as well as a primer for beginning students in the field. He considers such questions as how did primitive bacteria, pond scum, evolve into the complex life-forms found at the beginning of the Cambrian Period? How do scientists identify ancient microbes and what do these tiny creatures tell us about the environment of the early Earth? (And, in a related chapter, Schopf discusses his role in the controversy that swirls around recent claims of fossils in the famed meteorite from Mars.) Like all great teachers, Schopf teaches the non-specialist enough about his subject along the way that we can easily follow his descriptions of the geology, biology, and chemistry behind these discoveries. Anyone interested in the intriguing questions of the origins of life on Earth and how those origins have been discovered will find this story the best place to start.

Author Bio

Schopf, J. William : University of California, Los Angeles

J. William Schopf, a member of the Department of Earth and Space Sciences, the Molecular Biology Institute, and the Institute of Geophysics and Planetary Physics (IGPP) at the University of California, Los Angeles, is Professor of Paleobiology and Director of the IGPP Center for the Study of Evolution and the Origin of Life. A Member of the National Academy of Sciences, the American Philosophical Society, and the American Academy of Arts and Sciences, he is the recipient of medals from the National Science Board, the National Academy of Sciences, and the International Society for the Study of the Origin of Life. He has also been awarded national book prizes for two edited volumes on life's earliest evolution, an Alexander von Humboldt Senior Research Prize, and two Guggenheim Fellowships.

Prologue Acknowledgments

Chapter 1. Darwin's Dilemma

Breakthrough to the Ancient Past The Nature of Geologic Time The ''Schoolbook'' History of Life Darwin's Dilemma Denouement

Chapter 2. Birth of a New Field of Science

The Floodgates Crack Open Famous Figures Enter the Field A Youngster Joins the Fray The Floodgates Open Full Bore

Chapter 3. The Oldest Fossils and What They Mean

''Trust but Verify'' ''Real World Problems'' in the Search for Early Life Questions and Answers about the Oldest Records of Life The Oldest Fossils Known

Chapter 4. How Did Life Begin?

The Basics of Biology The Universals of Life How Did Monomers of CHON Arise on the Lifeless Earth? Organic Monomers beyond the Earth How Did Monomers Become Linked into Polymers? From Monomers to Polymers toward Life

Chapter 5. Metabolic Memories of the Earliest Cells

How Did Cells Begin? The Essentials of Life Life's Earliest Way to Make a Living Air and Light: A New Source of Glucose Why Do We Breathe Oxygen? The Four-Stage Development of Modern Metabolism

Chapter 6. So Far, So Fast, So Early?

How Old Is the Modern Ecosystem? When Did Life Begin? How Did Evolution Proceed So Far, So Fast, So Early? Paleobiology: Fossils, Geology, and Geochemistry Isotopic Evidence of Ancient Metabolisms Paleobiology: Direct Evidence of Early Evolution

Chapter 7. Stromatolites: Earth's First High-Rise Condos

Nature Is Not Compartmentalized Stromatolites: Earth's First High-Rise Condos Stromatolites of the Geologic Past What Are Stromatolites Good For?

Chapter 8. Cyanobacteria: Earth's Oldest ''Living Fossils''

Modes and Tempos in the Evolution of Life The Status Quo Evolution of Cyanobacteria Evolution's Most Successful Ecologic Generalists

Chapter 9. Cells Like Ours Arise at Last

Life Like Us Has Cells Like Ours DNA and Development: Keys to Eukaryotic Success How Old Are the Eukaryotes? Eukaryotes Perfect the Art of Cloning Sex: A New Lifestyle Brings Major Change The Wax and Wane of Precambrian Acritarchs Prelude to the Phanerozoic

One of the greatest mysteries in reconstructing the history of life on Earth has been the apparent absence of fossils dating back more than 550 million years. We have long known that fossils of sophisticated marine life-forms existed at the dawn of the Cambrian Period, but until recently scientists had found no traces of Precambrian fossils. The quest to find such traces began in earnest in the mid-1960s and culminated in one dramatic moment in 1993 when William Schopf identified fossilized microorganisms three and a half billion years old. This startling find opened up a vast period of time--some eighty-five percent of Earth's history--to new research and new ideas about life's beginnings. In this book, William Schopf, a pioneer of modern paleobiology, tells for the first time the exciting and fascinating story of the origins and earliest evolution of life and how that story has been unearthed.

Gracefully blending his personal story of discovery with the basics needed to understand the astonishing science he describes, Schopf has produced an introduction to paleobiology for the interested reader as well as a primer for beginning students in the field. He considers such questions as how did primitive bacteria, pond scum, evolve into the complex life-forms found at the beginning of the Cambrian Period? How do scientists identify ancient microbes and what do these tiny creatures tell us about the environment of the early Earth? (And, in a related chapter, Schopf discusses his role in the controversy that swirls around recent claims of fossils in the famed meteorite from Mars.) Like all great teachers, Schopf teaches the non-specialist enough about his subject along the way that we can easily follow his descriptions of the geology, biology, and chemistry behind these discoveries. Anyone interested in the intriguing questions of the origins of life on Earth and how those origins have been discovered will find this story the best place to start.

Author Bio

Schopf, J. William : University of California, Los Angeles

J. William Schopf, a member of the Department of Earth and Space Sciences, the Molecular Biology Institute, and the Institute of Geophysics and Planetary Physics (IGPP) at the University of California, Los Angeles, is Professor of Paleobiology and Director of the IGPP Center for the Study of Evolution and the Origin of Life. A Member of the National Academy of Sciences, the American Philosophical Society, and the American Academy of Arts and Sciences, he is the recipient of medals from the National Science Board, the National Academy of Sciences, and the International Society for the Study of the Origin of Life. He has also been awarded national book prizes for two edited volumes on life's earliest evolution, an Alexander von Humboldt Senior Research Prize, and two Guggenheim Fellowships.

Table of Contents

Prologue Acknowledgments

Chapter 1. Darwin's Dilemma

Breakthrough to the Ancient Past The Nature of Geologic Time The ''Schoolbook'' History of Life Darwin's Dilemma Denouement

Chapter 2. Birth of a New Field of Science

The Floodgates Crack Open Famous Figures Enter the Field A Youngster Joins the Fray The Floodgates Open Full Bore

Chapter 3. The Oldest Fossils and What They Mean

''Trust but Verify'' ''Real World Problems'' in the Search for Early Life Questions and Answers about the Oldest Records of Life The Oldest Fossils Known

Chapter 4. How Did Life Begin?

The Basics of Biology The Universals of Life How Did Monomers of CHON Arise on the Lifeless Earth? Organic Monomers beyond the Earth How Did Monomers Become Linked into Polymers? From Monomers to Polymers toward Life

Chapter 5. Metabolic Memories of the Earliest Cells

How Did Cells Begin? The Essentials of Life Life's Earliest Way to Make a Living Air and Light: A New Source of Glucose Why Do We Breathe Oxygen? The Four-Stage Development of Modern Metabolism

Chapter 6. So Far, So Fast, So Early?

How Old Is the Modern Ecosystem? When Did Life Begin? How Did Evolution Proceed So Far, So Fast, So Early? Paleobiology: Fossils, Geology, and Geochemistry Isotopic Evidence of Ancient Metabolisms Paleobiology: Direct Evidence of Early Evolution

Chapter 7. Stromatolites: Earth's First High-Rise Condos

Nature Is Not Compartmentalized Stromatolites: Earth's First High-Rise Condos Stromatolites of the Geologic Past What Are Stromatolites Good For?

Chapter 8. Cyanobacteria: Earth's Oldest ''Living Fossils''

Modes and Tempos in the Evolution of Life The Status Quo Evolution of Cyanobacteria Evolution's Most Successful Ecologic Generalists

Chapter 9. Cells Like Ours Arise at Last

Life Like Us Has Cells Like Ours DNA and Development: Keys to Eukaryotic Success How Old Are the Eukaryotes? Eukaryotes Perfect the Art of Cloning Sex: A New Lifestyle Brings Major Change The Wax and Wane of Precambrian Acritarchs Prelude to the Phanerozoic